Myeloproliferative disorders (MPDs), also known as myeloproliferative neoplasms (MPNs), are clonal stem cell disorders characterized by increased production of mature blood cells. MPDs/MPNs are a group of clonal myeloid neoplasms in which a genetic alteration occurs in a hematopoietic progenitor cell leading to its proliferation, resulting in an increase in the peripheral blood white blood cells (WBCs), red blood cells (RBCs), platelets, or a combination of these cells. MPNs are classified as rare diseases.
There are four main MPNs, namely chronic myelogenous leukemia (CML), atypical CML, polycythemia vera (PV), essential thrombocytosis (ET), and primary myelofibrosis (PMF). Additional MPNs include systemic mastocytosis, hypereosinophilic syndrome, chronic myelomonocytic leukemia, chronic neutrophilic leukemia (CNL), and chronic eosinophilic leukemia. In general, leukemia cells can be classified as MPNs.